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Geomorphology-oriented theoretical framework and construction method for value-added DEM

Journal of Geographical Sciences 2024年第1期34卷 165-184页

作者： ZHANG Haiping tang guoan XIONG Liyang YANG Xin LI Fayuan Key Laboratory of Virtual Geographic Environment Ministry of EducationNanjing Normal UniversityNanjing 210023China School of Geography Nanjing Normal UniversityNanjing 210023China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing 210023China

Digital elevation model(DEM)plays a fundamental role in the study of the earth system by expressing surface configuration,understanding surface process,and revealing surface mechanism.DEM is widely used in analysis and modeling in the field of geoscience.However,traditional DEM has the defect of single attribute,which is difficult to support the research in earth system science oriented to geoscience process and mechanism mining.Hence,realizing the value-added data model on the basis of traditional DEM is necessary to serve digital elevation modeling and terrain analysis under the background of a new geomorphology research paradigm and earth observation technology.A theoretical framework for value-added DEM that mainly includes concept,connotation,content,and categories,is constructed in this study.The relationship between different types of value-added DEMs as well as the research significance and application category of this theoretical framework are also proposed.The following are different methods of value-added DEMs:(1)value-added methods of DEM space and time dimensions that emphasize the integration of the ground and underground as well as coupling of time and space,(2)attribute-based value-added methods composed of material(including underground,surface,and ground)and morphological properties,and(3)value-added methods of features and physical elements that consider geographical objects and landform features formed by natural processes and artificial effects.The digital terrace,slope,and watershed models are used as examples to illustrate application scenarios of the three kinds of value-added methods.This study aims to improve expression methods of DEMs under the background of new surveying and mapping technologies by adding value to the DEM at three levels of dimensions,attributes,and elements as well as support knowledge-driven digital geomorphological analysis in the era of big data.

关键词： spatial data model value-added DEM digital terrain analysis geomorphological ontology geomorphology

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Research progress on metal-organic framework compounds(MOFs)in electrocatalysis

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Journal of Environmental Sciences 2024年第7期141卷 261-276页

作者： Yutong guo Shunzheng Zhao Xiaolong tang Honghong Yi Department of Environmental Science and Engineering School of Energy and Environmental EngineeringUniversity of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants Beijing 100083China

Metal-organic frameworks(MOFs)have favorable characteristics such as large specific surface area,high porosity,structural diversity,and pore surface modification,giving them great potential for development and attractive prospects in the research area of modern materials electrocatalysis.However,unsatisfactory catalytic activity and poor electronic conductivity are the main challenges facing MOFs.This review focuses on MOF-based materials used in electrocatalysis,based on the types of catalytic reactions that have used MOF-based materials in recent years along with their applications,and also looks at some new electrocatalytic materials and their future development prospects.

关键词： Metal-organic frame compounds Electrocatalysis Oxidation-reduction Nitrogen fixation to synthesize ammonia Carbon dioxide reduction

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Recent Advances in Mechanistic Understanding of Metal-Free Carbon Thermocatalysis and Electrocatalysis with Model Molecules

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Nano-Micro Letters 2024年第7期16卷 74-97页

作者： Wei guo Linhui Yu Ling tang Yan Wan Yangming Lin CAS Key Laboratory of Design and Assembly of Functional Nanostructures Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002People’s Republic of China Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials Xiamen Institute of Rare Earth MaterialsHaixi InstituteChinese Academy of SciencesXiamen 361021People’s Republic of China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002People’s Republic of China Institute of Urban Environment Chinese Academy of SciencesXiamen 361021People’s Republic of China

Metal-free carbon,as the most representative heterogeneous metal-free catalysts,have received considerable interests in electro-and thermo-catalytic reac-tions due to their impressive performance and sustainability.Over the past decade,well-designed carbon catalysts with tunable structures and heteroatom groups coupled with various characterization techniques have proposed numerous reaction mechanisms.However,active sites,key intermediate species,precise structure-activity relationships and dynamic evolution processes of carbon catalysts are still rife with controversies due to the monotony and limitation of used experimental methods.In this Review,we sum-marize the extensive efforts on model catalysts since the 2000s,particularly in the past decade,to overcome the influences of material and structure limitations in metal-free carbon catalysis.Using both nanomolecule model and bulk model,the real contribution of each alien species,defect and edge configuration to a series of fundamentally important reactions,such as thermocatalytic reactions,electrocatalytic reactions,were systematically studied.Combined with in situ techniques,isotope labeling and size control,the detailed reaction mechanisms,the precise 2D structure-activity relationships and the rate-determining steps were revealed at a molecular level.Furthermore,the outlook of model carbon catalysis has also been proposed in this work.

关键词： Metal-free carbon catalysts Model catalyst Electrocatalysis Active site Reaction mechanisms

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Macro Meso Response and Stress Wave Propagation Characteristics of MCT High-Voltage Switch Under Shock load

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Defence Technology（防务技术） 2024年第2期32卷 317-335页

作者： Yuyang guo Chuang Chen Ruizhi Wang Enling tang Key Laboratory of Transient Physical Mechanics and Energy Conversion Materials of Liaoning Province Shenyang Ligong UniversityShenyang110159LiaoningChina

In order to study the dynamic and electrical coupling response characteristics of Metal Oxide Semiconductor Controlled Thyristor(MCT)high-voltage switch under the synergic action of mechanical load and high voltage,the separated Hopkinson pressure bar(SHPB)test system was used to simulate different impact load environments,and combined with the multi-layer high-voltage ceramic capacitor charging and discharging system,the instantaneous electrical signals of MCT high-voltage switch were collected.Combined with numerical simulation and theoretical analysis,the failure mode and stress wave propagation characteristics of MCT high voltage switch were determined.The mechanical and electrical coupling response characteristics and failure mechanism of MCT high voltage switch under dynamic load were revealed from macroscopic and microscopic levels.The results show that the damage modes of MCT high-voltage switches can be divided into non-functional damage,recoverable functional damage,non-recoverable damage and structural damage.Due to the gap between the metal gate and the oxide layer,the insulating oxide layer was charged.After placing for a period of time,the elastic deformation of the metal gate partially recovered and the accumulated charge disappeared,which induced the recoverable functional damage failure of the device.In addition,obvious cracks appeared on both sides of the monocrystalline silicon inside the MCT high-voltage switch,leading to unrecoverable damage of the device.

关键词： MCT Impact load Failure analysis Stress wave Numerical simulation

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Nutrition impacts of non-solid cooking fuel adoption on under-five children in developing countries

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Journal of Integrative Agriculture 2024年第2期23卷 397-413页

作者： Yalin tang Yuhe guo Gang Xie Chengfang Liu China Center for Agricultural Policy School of Advanced Agricultural SciencesPeking UniversityBeijing 100871China Agricultural Information Institute Chinese Academy of Agricultural SciencesBeijing 100081China

This paper examines the nutrition impacts of using non-solid cooking fuel on under-five children in developing countries.We draw on data from more than 1.12 million children in 62 developing countries from the Demographic and Health Surveys(DHS).Results from both fixed effects(FE)and instrumental variable(IV)estimates show that using non-solid cooking fuel significantly improves the nutrition outcomes of under-five children.Compared with their peers from households mainly using solid fuel,children from households mainly using non-solid fuel exhibit a lower probability of experiencing stunting(by 5.9 percentage points)and being underweight(by 1.2 percentage points).Our further investigation provides evidence for several underlying mechanisms,such as improved indoor air quality,induced reduction in children’s respiratory symptoms,benefits on maternal health,and reduction in maternal time spent on fuel collection or cooking.Heterogenous analyses suggest that the nutrition benefits of using non-solid cooking fuel are more prominent among boys,children above three years old,and those from households of lower socioeconomic status,rural areas,and Southeast Asia.

关键词： non-solid cooking fuel nutrition benefits under-five children developing countries

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Theoretical study on magnetocaloric effect and its electric-field regulation in CrI_(3)/metal heterostructure

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Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 134-141页

作者： Weiwei He Ziming tang Qihua Gong Min Yi Wanlin guo State Key Laboratory of Mechanics and Control for Aerospace Structures Key Laboratory for Intelligent Nano Materials and Devices of Ministry of EducationInstitute for Frontier ScienceNanjing University of Aeronautics and AstronauticsNanjing 210016China MIIT Key Laboratory of Aerospace Information Materials and Physics College of PhysicsNanjing University of Aeronautics and AstronauticsNanjing 211106China

The extraordinary properties of a heterostructure by stacking atom-thick van der Waals(vdW)magnets have been extensively studied.However,the magnetocaloric effect(MCE)of heterostructures that are based on monolayer magnets remains to be explored.Herein,we deliberate MCE of vd W heterostructure composed of a monolayer CrI_(3)and metal atomic layers(Ag,Hf,Au,and Pb).It is revealed that heterostructure engineering by introducing metal substrate can improve MCE of CrI_(3),particularly boosting relative cooling power to 471.72μJ m^(-2)and adiabatic temperature change to 2.1 K at 5 T for CrI_(3)/Hf.This improved MCE is ascribed to the enhancement of magnetic moment and intralayer exchange coupling in CrI_(3)due to the CrI_(3)/metal heterointerface induced charge transfer.Electric field is further found to tune MCE of CrI_(3)in heterostructures and could shift the peak temperature by around 10 K in CrI_(3)/Hf,thus manipulating the working temperature window of MCE.These theoretical results could enrich the research on low-dimensional magnetocaloric materials.

关键词： magnetocaloric effect heterostructure metal substrate

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Wide‑field swept‑source OCT angiography of the periarterial capillary‑free zone before and after anti‑VEGF therapy for branch retinal vein occlusion

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Eye and Vision 2024年第2期10卷 31-40页

作者： Wenyi tang Wei Liu Jingli guo Lili Zhang Gezhi Xu Keyan Wang Qing Chang Department of Ophthalmology Eye and ENT Hospital of Fudan University83 Fenyang RoadShanghai 200031China Shanghai Key Laboratory of Visual Impairment and Restoration Fudan UniversityShanghaiChina NHC Key Laboratory of Myopia(Fudan University) Laboratory of MyopiaChinese Academy of Medical SciencesShanghaiChina

Background:The aim of the study was to investigate the changes in the periarterial capillary-free zone(paCFZ)after anti-vascular endothelial growth factor(VEGF)therapy in patients with branch retinal vein occlusion(BRVO)by widefield swept-source optical coherence tomography angiography(SS-OCTA)and assess their associations with clinical outcomes.Methods:In this retrospective observational study of 54 treatment-naive BRVO patients with macular edema,we reviewed the findings of 12×12 mm^(2)SS-OCTA at baseline,3,6,and 12 months after intravitreal ranibizumab injections.The paCFZ and major retinal artery areas were measured on SS-OCTA images.The paCFZ area to artery area(P/A)ratio was calculated.Results:The paCFZ areas and P/A ratios of first-and second-order arteries were significantly greater in BRVO eyes than in contralateral eyes(all P<0.01),but there were no differences in the first-and second-order artery areas(P=0.20 and 0.25,respectively).The paCFZ areas and P/A ratios decreased significantly at 3,6,and 12 months after anti-VEGF therapy(all P<0.01).The baseline P/A ratio was significantly correlated with the baseline best-corrected visual acuity(BCVA),central retinal thickness,and their improvements at 3,6,and 12 months(all P<0.05).Baseline BCVA and P/A ratios of first-and second-order arteries were independently associated with the final BCVA in multivariate linear regression.Conclusions:Wide-field SS-OCTA shows that anti-VEGF therapy can lead to a significant improvement in the paCFZ parameters in BRVO.Smaller baseline P/A ratios on SS-OCTA tend to predict better visual outcomes at 12 months after anti-VEGF therapy.

关键词： Swept-source optical coherence tomography angiography Branch retinal vein occlusion Periarterial capillary free zone Anti-VEGF treatment Prognosis

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Cationic Conjugated Oligomers for Efficient and Rapid Antibacterial Photodynamic Therapy via Both Type Ⅰ and Type Ⅱ Pathways

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Chinese Journal of Chemistry 2024年第1期42卷 61-66页

作者： Huan Wang Shuwen guo Qiong Yuan Meiqi Li Yanli tang Country Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province Key Laboratory of Applied Surface and Colloid ChemistryMinistry of EducationSchool of Chemistry and Chemical EngineeringShaanxi Normal UniversityXi'anShaanxi 710119China

Recently,photodynamic therapy(PDT)has attracted wide attention due to its less susceptibility to drug resistance,broad-spectrum biocidal activity and biosafety in normal tissues.However,the traditional photosensitizers(Ps)face the disadvantage of poor therapeutic efficacy due to the requirement of an aerobic environment to generate ^(1)O_(2) through Type Ⅱ pathway.Herein,we designed and synthesized a novel cationic conjugated oligomer oligo(phenylene vinylene)(OPV)and studied its antibacterial photodynamic activity against both Gram-negative Escherichia coli(E.coli)and Gram-positive bacteria methicillin-resistant Staphylococcus aureus(MRSA).Importantly,the OpV can rapidly produce reactive oxygen species(ROs)through double pathways,Type Ⅰ and Ⅱ mechanism under white light irradiation,and efficiently kill E.coli and MRSA at a nanomolar level.The dual type photosensitizing capability makes OPV promising for enhanced PDT to treat pathogens and tumors in complex environments.

关键词： Conjugated oligomers Antibacterial photodynamic therapy Oligo(phenylene vinylene) Reactive oxygen species Typelandll pathways

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Conceptual design of a 714-MHz RFQ for compact proton injectors and development of a new tuning algorithm on its aluminium prototype

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Nuclear Science and Techniques 2024年第1期35卷 45-58页

作者： Yi-Xing Lu Wen-Cheng Fang Yu-Sen guo Zhen-tang Zhao Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800China University of Chinese Academy of Sciences Beijing 101408China Shanghai Advanced Research Institute Chinese Academy of Sciences Shanghai 201204China Shanghai Key Laboratory of Cryogenics&Superconducting RF Technology Shanghai 201800China ShanghaiTech University Shanghai 201210China

Radio frequency quadrupoles(RFQs),which are crucial components of proton injectors,significantly affect the performance of proton accelerator facilities.An RFQ with a high frequency of 714 MHz dedicated to compact proton injectors for medi-cal applications is designed in this study.The RFQ is designed to accelerate proton beams from 50 keV to 4 MeV within a short length of 2 m and can be matched closely with the downstream drift tube linac to capture more particles through a preliminary optimization.To develop an advanced RFQ,challenging techniques,including fabrication and tuning method,must be evaluated and verified using a prototype.An aluminium prototype is derived from the conceptual design of the RFQ and then redesigned to confirm the radio frequency performance,fabrication procedure,and feasibility of the tuning algorithm.Eventually,a new tuning algorithm based on the response matrix and least-squares method is developed,which yields favorable results based on the prototype,i.e.,the errors of the dipole and quadrupole components reduced to a low level after several tuning iterations.Benefiting from the conceptual design and techniques obtained from the prototype,the formal mechanical design of the 2-m RFQ is ready for the next manufacturing step.

关键词： Compact proton injector RFQ IH-DTL High gradient Tuning

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Cyber-Physical Resilience Enhancement for Power Transmission Systems with Energy Storage Systems

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 844-855页

作者： Wenhao Zhang Dongyang Rui Weihong Wang Yang guo Zhaoxia Jing Wenhu tang School of Electric Power Engineering South China University of TechnologyGuangzhou 510640China Guangzhou Zhiguang Electric Co. Ltd and Zhiguang Research Institute(Guangzhou)Co.LtdGuangzhou 510765China

In a power system, when extreme events occur, such as ice storm, large scale blackouts may be unavoidable. Such small probability but high risk events have huge impact on power systems. Most resilience research in power systems only considers faults on the physical side, which would lead to overly idealistic results. This paper proposes a two-stage cyber-physical resilience enhancement method considering energy storage (ES) systems. The first stage calculates optimal planning of ES systems, and the second stage assesses resilience and enhancement of ES systems during the disaster. In the proposed model, cyber faults indirectly damage the system by disabling monitoring and control function of control center. As a result, when detection and response process of physical faults are blocked by cyber failures, serious load shedding occurs. Such a cyber-physical coupling mechanism of fault, response, restoration process is demonstrated in the modified IEEE Reliable Test System-79 (RTS-79). Simulation results show compared with the physical-only system, the cyber-physical system has a more accurate but degraded resilient performance. Besides, ES systems setting at proper place effectively enhance resilience of the cyber-physical transmission system with less load Shedding.

关键词： Cyber-physical faults energy storage systems resilience enhancement transmission systems

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